[BRENT in 10-uh-C]

Generally speaking, I always heard of water being used to clean carbon. If the engine was hot and revved, water was poured down the carburetor (-or thru a vacuum port) which made steam in the combustion chamber. Just like steam cleaning grease, it removed carbon rather quickly.


Now I have seen engines that were flooded having a match dropped down the carburetor while the engine is being started. With puddled gasoline laying in the floor of the intake, it would ignite and the flames would be pulled into the cylinder before being extinguished on its own. This works remarkably well but is not for the faint of heart.



One other trick I have seen on early brass-era stuff that have long intakes that don't vaporize well when cold, is my dad would take an oxy/acetylene torch and turn the gas and a little oxygen on. Without lighting it he would stick the torch tip into the carburetor inlet. The gas and oxygen would rise in the intake and as the engine was hand-cranked, the lighter gas would ignite easier. The engine would start on the acetylene and almost immediately the gasoline would start vaporizing. As soon as enough gasoline was being drawn up the intake, the exhaust would start rolling black smoke. At that time the torch was removed. I remember asking several times about what would happen if it backfired and lit the torch. Dad always said you will hear it and that is your cue to turn off the torch. He said the oxygen was not turned on enough to make a super hot fire. I guess it makes sense, and I never did see one backfire thru the carb. I have told this same story and tractor guys used to do it when they were cold starting on kerosene or tractor fuel.

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